A kind of process of Inner Spiral Surface inner high voltage mold filling bulging
The present invention relates to a kind of process of Tube Hydroforming, particularly relate to a kind of process of Inner Spiral Surface inner high voltage mold filling bulging.
Screw drilling tool motor and screw pump are the screw machines of extensive use in petroleum industry, and its stator and rotor have formed the poor Meshing Pair of a tooth, and their Design and manufacture quality directly affects the property indices of screw machine.Stator is comprised of metal shell and rubber bushing, rubber bushing spiral camber and the engagement of rotor helical-screw curved surface.Traditional stator is to generate at the inwall injecting glue of metallic cylinder the rubber layer spiral camber that does not wait wall thickness; Novel stator is in preprocessing, to have the wall thickness rubber layer spiral cambers such as metal stator inwall injecting glue generation of Inner Spiral Surface.The inner surface of Novel stator metal-back need to be processed into Inner Spiral Surface, and because such part is elongated and be complicated inner surface, its processing lacks efficient processing method and manufacturing equipment.Existing process equipment is complicated, and cost is high, and efficiency is low.
The forming high pressure in pipe technology of the light body structure part of hollow variable cross-section developing based on lightweight and integrated feature is applicable to the hollow parts of circle, rectangle or odd-shaped cross section that processing changes along member axis direction.Hydroforming refers to and utilizes liquid as power transmission medium, to make a kind of moulding process technology of component shaping.In order to adapt to the requirement of modern industry to high-quality, lightweight and low-cost part, as process important in a kind of metal forming, hydroforming is developed rapidly.Because the method utilizes liquid as medium or mould, therefore can pass through the real-time control to liquid medium, realize the accurate control to technological parameter, and liquid as power transmission medium, can also to save moulding die needed.Hydraulic expanding-forming in the past has two kinds: 1. bulging pipe fitting is thin-walled, by hydraulic expanding-forming, obtains required given shape; 2. large wall thickness workpiece free bulge, does not need to obtain specific complicated shape, and as generator guard ring bulging, object is to improve the mechanical property of workpiece.
Summary of the invention
The object of the present invention is to provide a kind of process of Inner Spiral Surface inner high voltage mold filling bulging, the method is for waiting inner high voltage mold filling bulging of wall thickness rubber layer stator metal-back curved surface, in order to realize the highly-efficient processing of helical stator metal-back inner helical surface, a kind of process of inner high voltage mold filling bulging is provided, is applicable to the shaping processing of the smooth inside spin pipe fitting of large helical pitch.
The object of the invention is to be achieved through the following technical solutions:
A process for Inner Spiral Surface inner high voltage mold filling bulging, described method comprises preparatory stage, free bulge stage, mold filling bulging stage three Main Stage; Its technical process: first workpiece is located, clamped on workbench, sealing device is sealed at both ends by workpiece, electric heater unit starts, and workpiece is heated to 200 ℃ of left and right; Inside workpiece injects highly pressurised liquid, and workpiece starts free bulge, and then, electric heater unit shifts out workbench after opening, Inner Spiral Surface mould matched moulds; Finally, increase inside workpiece filling liquid pressure, workpiece enters the mold filling bulging stage, when checkout gear detects workpiece, pastes after mould completely, pressurize 5-10 minute, after completing, hydraulic system off-load, workbench tilts liquid is refluxed fast, and sealing device is opened, and takes off workpiece.
Advantage of the present invention and effect are:
(1) apparatus structure of process using is simple, and cost is low, has realized shaping processing (2) this process of Inner Spiral Surface pipe fitting and the highly-efficient processing that device can be realized helical stator shell Inner Spiral Surface, than existing process technology, improves working (machining) efficiency several times.(3) this process and device can be applied to the production of other Inner Spiral Surface pipe fittings.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of bulging process device of the present invention.
The specific embodiment
Below in conjunction with accompanying drawing illustrated embodiment, the invention will be further described.
The present invention is applied to hydroforming to wait the shaping processing of wall thickness rubber layer stator metal-back, proposes a kind of Inner Spiral Surface inner high voltage mold filling bulging process method.The Inner Spiral Surface bulging of stator of the present invention does not belong to the bulging of thin-walled parts, and object is but the complex surface that has certain size and geometric accuracy in order to obtain.Helical stator Inner Spiral Surface is smooth surface, and has large helical pitch feature, and in Bulging Process, the suffered axial constraint power of workpiece is little.Bulging process has the impact that is not subject to the elongated geometric properties of workpiece, the controlled and high feature of working (machining) efficiency of process.Although the matching allowance between stator and rotor has important impact to the performance of screw machine, owing to generally can pouring into a mould one deck rubber layer between metal stator and rotor, how much profiles of spiral camber allow to exist certain error.Therefore, the processing of helical stator Inner Spiral Surface is not very high for the requirement of geometric accuracy, and the geometric accuracy that type that mold filling is swollen obtains can meet production requirement.
Technical process is divided into preparatory stage, free bulge stage, mold filling bulging stage three Main Stage.First workpiece is located, clamped on workbench, sealing device is sealed at both ends by workpiece, and electric heater unit starts, and workpiece is heated to 200 ℃ of left and right; Inside workpiece injects highly pressurised liquid, and workpiece starts free bulge.Then, electric heater unit shifts out workbench after opening, Inner Spiral Surface mould matched moulds; Finally, increase inside workpiece filling liquid pressure, workpiece enters the mold filling bulging stage, pastes after mould pressurize 5-10 minute when checkout gear detects workpiece completely.After completing, hydraulic system off-load, workbench tilts liquid is refluxed fast, and sealing device is opened, and takes off workpiece.It is more than the main technique part of forming process.
The present invention is applicable to being applied to the spiral camber processing in elongate cylinder hole, has certain machining accuracy and higher working (machining) efficiency.
Parts in figure: 1-running fix seal head 2-metal pipe billet 3-Inner Spiral Surface mould 4-stationary positioned seal head 5-heating plate.
As shown in Figure 1: machine is installed to metal pipe billet (2) on workbench, by running fix seal head (1) and stationary positioned seal head (4), tubing is positioned, pass through conical surface seal.Location sealing head (1), by Driven by Hydraulic Cylinder, applies axial force to workpiece, to guarantee sealing state and the axial force in Bulging Process in Bulging Process.Location sealing head (1) injects highly pressurised liquid by centre bore tubing is carried out to bulging.Bulging liquid is high pressure-temperature hot liquid, and high temperature is more easily out of shape tubing.The heating of pipe fitting and liquid is heated by semicircle heating plate (5), carries out free bulge after heating, and before matched moulds, heater shifts out workbench.
Bulging is divided into free bulge and matched moulds bulging.The free bulge stage does not add mould, allows tubing free wxpansion.Reasonable coordination by axial force and hydraulic coupling makes tubing reach good shape.When displacement transducer detects tubing free bulge to workpiece path size d, start to carry out matched moulds bulging.Inner Spiral Surface mould (3) carries out matched moulds by Hydraulic Cylinder, and is provided with special lockable mechanism.Mould is divided into symmetrical two parts, and its inner surface is the outer equidistant surface of workpiece spiral camber, and equidistant radius is thickness of workpiece.Under the effect of continuing of the hydraulic coupling of workpiece in die pressure and tubing, paste mould.After workpiece outer wall and the laminating of dies cavity groove, trigger and paste mould sensor, stop inner high voltage pressure process, carry out pressurize.
Different with material according to workpiece dimension, carry out pressurize and process about 5-10 minute, make the further flow distribution of material, can make bulging more abundant, improve near the shaping of helicoid groove and paste mould.